Images formed by an object placed between two plane mirrors whose reflecting surfaces make an angle of $90^o$ with one another lie on

The angle made by the incident ray of light with the reflecting surface is called:

By what angle should $M_2$ be rotated,so that the light ray after reflection from both mirrors becomes horizontal? (The angle of incidence at mirror $M_1$ is $40^{\circ}$ and the angle between $M_2$ and the horizontal is $25^{\circ}$ as shown in the figure.)

Two plane mirrors are parallel to each other and an object $O$ is placed between them. Then the distance of the first three images from the mirror $M_2$ will be (in $cm$):

When an object is placed between two parallel mirrors,the number of images formed is:

$A$ ray is reflected in turn by three plane mirrors mutually at right angles to each other. The angle between the incident and the reflected rays is......$^o$